Known tape printers may be divided into two types: tape printers for use with a cassette which houses both a print receiving medium (hereinafter referred to as a tape which may be a continuous tape or may comprise a web carrying die cut labels) and a print forming medium (hereinafter referred to as an ink ribbon); and tape printers which are arranged for use with a cassette housing the tape and a separate cassette housing the ink ribbon. The advantage of the latter arrangement is that the ink ribbon cassette may be replaced with another cassette containing ink ribbon of either the same or a different type without replacing the tape cassette. This is advantageous in, for example, multicolored printing in which the ink ribbon cassette may be replaced with another cassette containing ink ribbon of a different color. Alternatively, the tape cassette may be replaced without replacing the ink ribbon cassette. This feature is advantageous if a different type of tape is required, such as a tape of a different width or a tape comprising a different material. Furthermore, a single ink ribbon cassette may be used for a plurality of tape cassettes with the ink ribbon in the ink ribbon cassette being longer than the tape in the tape cassette.
In this specification, systems which use a cassette containing both the tape and ink ribbon are referred to as D1-type systems and systems which use separate tape and ink ribbon cassettes are referred to as D2-type systems.
The most common arrangement for both D1 and D2 type systems comprises a tape printer having a cassette receiving portion in an upper surface thereof. The cassette receiving portion houses a printhead and a platen.
In known D1-type systems the cassette housing the tape and ink ribbon is inserted into the receiving portion from a top side in a direction which is parallel to an axis of rotation of the platen and also parallel to a line of print elements on the printhead such that when the cassette is received by the cassette receiving portion, the tape and the ink ribbon pass in overlap between the printhead and platen with the ink ribbon on the same side of the tape as the printhead. On receiving the cassette in the cassette receiving portion, the printhead and/or the platen roller are moveable so as to pinch the ink ribbon and tape therebetween for printing.
In known D2-type arrangements the printer comprises a cassette receiving portion for receiving the tape cassette and the ink ribbon cassette. The cassette receiving portion houses a platen and a printhead and the tape cassette and the ink ribbon cassette are inserted from a top side in a direction parallel to an axis rotation of the platen and also parallel to a line of printing elements on the printhead. When received in the cassette receiving portion, the tape and the ink ribbon pass in overlap between the printhead and the platen with the printhead and/or the platen being moveable so as to pinch the tape and ink ribbon therebetween for printing.
A disadvantage of this type of vertical loading arrangement is that the tape and/or ink ribbon may catch on elements of the printer such as the printhead and/or platen thus damaging the tape and/or ink ribbon. Furthermore, the cassettes used in such arrangements have portions of the tape/ink ribbon extending outside the housing of the cassette. Accordingly, the tape and/or ink ribbon may be damaged during storage as well as during use.
A D1-type arrangement which seeks to solve the above identified problem is disclosed in U.S. Pat. No. 5,435,657. This patent discloses a printer for use with a cartridge housing an ink ribbon and tape. A platen is provided in the cassette which co-operates with the tape and ink ribbon, the tape being disposed on a side closest to the platen relative to the ink ribbon. The printer has an opening on a side thereof for receiving the cassette which may be laterally inserted into the printer. When laterally inserted into the printer, the platen of the cassette operates with a printhead in the printer and a gear on the platen co-operates with a gear in the printer for advancing the tape and ink ribbon.
WO 99/44834 discloses a D2-type printer in which an ink ribbon cassette is laterally insertable in a side thereof. The tape is supplied as a spool which is insertable in a spool receiving portion from a top side of the printer. The printer houses a printhead and a platen for co-operation with the tape and ink ribbon which pass therebetween. In the arrangement disclosed in WO 99/44834 the platen and printhead are arranged such that the axis of rotation of the platen and a line of print elements on the printhead are parallel to the direction of insertion of the ink ribbon cassette. Accordingly, the above described problem of the ink ribbon catching the platen and/or the printhead remains in this arrangement. Furthermore, as the tape is not housed in a cassette it may be damaged during storage and use.